1. Field of the Invention
This invention relates to a method and apparatus of gain-determining and, more particularly, to a gain-determining method and a related apparatus for adjusting the grayscale white balance of a display apparatus.
2. Description of the Prior Art
With the progress of the technology and art of manufacturing, display apparatuses such as television also evolve continuously. The transition from analog form to digital form allows the application of image signals to be more broad and abounding. The panel for displaying images is also changed from heavy CRT to thin LCD and PDP. In the meanwhile, the size of panels also tends to be larger and larger. When the size of a panel is enlarged, the performance of image resolution of the panel becomes more important. In the performance of color, the saturation of color, the chromatic value, and the luminance are major factors which determine the quality of a display apparatus.
The image processing technology nowadays divides the displaying area on the panel into several pixel areas, and every pixel area has a red pixel, a green pixel, and a blue pixel. Because the color of all visible light can be generated by mixing red light, green light, and blue light, a pixel can display the desired color by controlling the light and shade of the red pixel, the green pixel, and the blue pixel. Due to factors such as the material of a panel and its manufacturing process, the color performance of every display apparatus is different. after assembling. In order to keep the color performance correct and uniform before exporting, the grayscale white balance of every display apparatus must be adjusted.
The adjusting method of grayscale white balance is: first, display a white image on the display apparatus; then, adjust the gains of sharpness of red color, green color, and blue color to make the chromatic values and luminance of the white image, obtained by mixing the three colors, approach the chromatic values and luminance of a target white image, that is to adjust the white image within a certain range of color temperature and color differences.
In prior art, the adjusting of grayscale white balance is mostly achieved by adjusting the gains of the sharpness of the red color, green color, and blue color by hand. However, adjusting by hand wastes a lot of time; at the same time, the difference between operations of people makes it difficult to achieve uniform quality of each product. Due to these defects in the prior art, the inventor provides the invention to improve the adjusting process for promoting the manufacturing capability and quality.